Direct driving apparatus for washing machine

ABSTRACT

A direct driving apparatus for a washing machine according to the present invention, capable of deceleration driving, includes a tub, a stator assembly coupled to the tub and a rotor assembly positioned outside the stator assembly, wherein the apparatus further includes a deceleration coupling unit positioned in a central space of the stator assembly.

TECHNICAL FIELD

The present invention relates to a driving apparatus for a washingmachine. More specifically, the present invention relates to a noveldriving apparatus for a washing machine, capable of driving bydecelerating the rotation of a motor in a direct driving apparatus for awashing machine.

BACKGROUND ART

In general, the washing machine is classified into a pulsator typewashing machine and a drum type washing machine. A pulsator type washingmachine and a drum type washing machine are driven in different ways.For example, the driving apparatus used for a pulsator type washingmachine is disclosed in Korean Patent No. 10-1603210 and Korean PatentLaid-open Nos. 10-2004-0071404 and 10-2004-0071417; and the drivingapparatus used for a drum type washing machine is disclosed in KoreanPatent Laid-open Nos. 10-2017-0010031, 10-2015-0009345 and10-2013-0091589.

In the case of a pulsator type washing machine, a washing tub is fixed,and a pulsator installed in the center of the washing tub rotates so asto generate the flow of water in the washing or rinsing mode and wash orrinse laundry. The pulsator is rotated by a washing shaft. The pulsatoris to be rotated at low speed and high torque in the washing and rinsingmode, while the washing tub is to be rotated at high speed and lowtorque in the dewatering mode. To this end, the pulsator type washingmachine has a decelerator for controlling the rotation speed and torqueof a motor, and the decelerator is operated by a clutch.

In the case of a drum type washing machine, a direct driving apparatusis widely used, in which a motor is fixed to a tub, and a washing tub(drum) installed in the tub is connected directly to the motor, therebyrotating the washing tub by rotation of the motor. In the direct drivingapparatus, the rotation speed of the motor is controlled to provide theRPM required for washing, rinsing and dewatering modes.

Since the rotation shaft of the motor directly rotates the washing tubin the direct driving apparatus, the operation of the motor in thewashing or rinsing mode at a low speed becomes inefficient. However, itis difficult to apply a clutch or decelerating device used for thepulsator type washing machine because of the structural characteristicsor limitations of the drum type washing machine and direct drivingapparatus.

Accordingly, the present inventors suggest a driving apparatus for awashing machine of a new structure in which a decelerator is applied toa direct driving apparatus, in order to solve the above-mentionedproblems.

DISCLOSURE OF INVENTION Technical Problem

It is an object of the present invention to provide a driving apparatusfor a washing machine of a new structure.

It is another object of the present invention to provide a drivingapparatus for a washing machine with high driving efficiency by applyingthe structure of a decelerator to the driving apparatus of a drum typewashing machine.

It is an object of the present invention to provide a driving apparatusfor a washing machine of a new structure.

It is another object of the present invention to provide a drivingapparatus for a washing machine with high driving efficiency by applyingthe structure of a decelerator to the driving apparatus of a drum typewashing machine.

The objects above of the present invention and other objects includedtherein may be easily achieved by the present invention explained in thefollowing.

Solution to Problem

A direct driving apparatus for a washing machine according to thepresent invention, capable of deceleration driving, includes a tub, astator assembly coupled to the tub and a rotor assembly positionedoutside the stator assembly, wherein the apparatus further includes adeceleration coupling unit positioned in a central space of the statorassembly.

According to the present invention, it is preferable that thedeceleration coupling unit includes a carrier, wherein the carrier has aplurality of planetary gears installed therein and includes a shaftreceiver having a carrier spline on the inside.

According to the present invention, it is preferable that the drivingapparatus for a washing machine further includes a shaft penetrating thecarrier and rotor assembly, wherein the shaft has a shaft spline formedin a position fitting into the carrier spline.

According to the present invention, the deceleration coupling unit mayfurther include a coupling housing receiving the carrier inside andhaving an inner gear engaged with the outer portions of the plurality ofplanetary gears.

According to the present invention, it is preferable that a lever unitis coupled to an insulator of the stator assembly such that the leverunit moves the coupling housing frontward or rearward.

According to the present invention, it is preferable that the shaftpenetrates through a shaft penetration of a sun gear protrudingfrontward in the rotor assembly.

According to the present invention, it is preferable that the sun gearhas an outer shape to be engaged with the inner portions of theplurality of planetary gears.

Advantageous Effects of Invention

The present invention has the effect of providing a driving apparatusfor a washing machine capable of utilizing the optimal decelerationratio in a washing or rinsing mode by applying the structure of adecelerator to a direct driving apparatus of a washing machine, therebymaximizing energy efficiency.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a rear perspective view illustrating the driving apparatus fora washing machine according to the present invention;

FIG. 2 is a front perspective view illustrating the driving apparatusfor a washing machine according to the present invention;

FIG. 3 is a rear perspective view illustrating the tub separated fromthe driving apparatus for a washing machine according to the presentinvention;

FIG. 4 is a front perspective view illustrating the tub separated fromthe driving apparatus for a washing machine according to the presentinvention;

FIG. 5 is an exploded perspective view illustrating the drivingapparatus for a washing machine according to the present invention;

FIG. 6 is a front perspective view illustrating the decelerationcoupling unit of the driving apparatus for a washing machine accordingto the present invention;

FIG. 7 is a rear perspective view illustrating the deceleration couplingunit of the driving apparatus for a washing machine according to thepresent invention;

FIG. 8 is an exploded perspective view illustrating the decelerationcoupling unit of the driving apparatus for a washing machine accordingto the present invention;

FIG. 9 is a perspective view illustrating the stator assembly of thedriving apparatus for a washing machine according to the presentinvention;

FIG. 10 is a side view illustrating the principle of operating the leverunit of the driving apparatus for a washing machine according to thepresent invention;

FIG. 11 is a side view illustrating the operation of the lever unit anddeceleration coupling unit of the driving apparatus for a washingmachine according to the present invention in a washing or rinsing mode;

FIG. 12 is a side view illustrating the operation of the lever unit anddeceleration coupling unit of the driving apparatus for a washingmachine according to the present invention in a dewatering mode;

FIG. 13 is a perspective view illustrating the rotor assembly of thedriving apparatus for a washing machine according to the presentinvention;

FIG. 14 is a cross-sectional view illustrating the rotor assembly of thedriving apparatus for a washing machine according to the presentinvention;

FIG. 15 is a cross-sectional view illustrating the structure when thedriving apparatus for a washing machine according to the presentinvention operates in a washing or rinsing mode; and

FIG. 16 is a cross-sectional view illustrating the structure when thedriving apparatus for a washing machine according to the presentinvention operates in a dewatering mode.

Hereinafter, the present invention will be described in detail withreference to the accompanying drawings.

MODE FOR THE INVENTION

FIG. 1 is a rear perspective view illustrating the driving apparatus 1for a washing machine according to the present invention, FIG. 2 is afront perspective view illustrating the driving apparatus 1, FIG. 3 is arear perspective view illustrating the tub 10 separated from the drivingapparatus 1 for a washing machine according to the present invention,and FIG. 4 is a front perspective view illustrating the tub 10.

As illustrated in FIG. 1 to FIG. 4, the driving apparatus 1 for awashing machine according to the present invention includes a tub 10, adeceleration coupling unit 20, a stator assembly 30 and a rotor assembly40.

The tub 10 is fixedly installed in the body (or cabinet) (notillustrated) of a washing machine. The end of a shaft 11 is positionedby penetrating the center of the tub 10 frontward. For reference, theterms “front/frontward” and “rear/rearward” as used herein refer todirections towards the tub 10 and the rotor assembly 40, respectively,with respect to the positions of the tub 10 and rotor assembly 40.

The shaft 11 is rotated by the rotation driving force of a motortransmitted through the deceleration coupling unit 20. For reference,the term “motor” as used herein denotes the stator assembly 30 and rotorassembly 40 together. As illustrated in FIG. 4, the decelerationcoupling unit 20 is positioned in the stator assembly 30, the rotationof the rotor assembly 40 allows the deceleration coupling unit 20 torotate, and the rotation of the deceleration coupling unit 20 causes theshaft 11 to rotate. The deceleration coupling unit 20 is switchedbetween a normal operating mode and a deceleration operating mode byoperation of a lever unit 300. In the normal operating mode, therotation speed of the rotor assembly 40 is the same as the rotationspeed of the shaft 11, and accordingly a dewatering mode at a high speedis applied. In the deceleration operating mode, the rotation speed ofthe rotor assembly 40 is slower than the rotation speed of the shaft 11,and accordingly a washing or rinsing mode at a low speed is applied.

A washing tub (or drum) (not illustrated) coupled to the end of theshaft 11 is positioned in front of the tub 10 thereinside. A tub bearinginsert 101 is formed in the front side of the center of the tub 10. Atub bearing 12 coupled to the tub bearing insert 101 supports therotation of the shaft 11. A lever unit positioning space 102 is formedradially outward from the center in the rear of the tub 10, and thespace extends to an opening 102 a in the lateral surface of the tub. Afirst lever 320 of the lever unit 300 is positioned in the lever unitpositioning space 102. The first lever 320 may be connected with a drainvalve motor (not illustrated) installed in one side of the tub by aseparate wire (not illustrated), etc., extending through the lever unitpositioning space 102 and opening 102 a. The drain valve motor cancontrol a drain valve and also control the operation of the lever unit300.

Referring to FIG. 3, a motor coupling 103 is protrudingly formed in thecenter of the rear of the tub 10 to couple the stator assembly 30. Aplurality of arranging protrusions 103 a and coupling holes 103 b areformed in the motor coupling 103. The arranging protrusion 103 a iscoupled to an arranging hole 34 in the stator assembly 30 such that thestator assembly 30 is positioned in the tub 10 at the correct position.The coupling hole 103 b communicates with a coupling hole 35 formed inthe stator assembly 30 such that the stator assembly 30 is coupled tothe tub 10 by a separate fastening means such as a bolt.

A shaft penetration 104 through which the shaft penetrates is formed inthe center of the tub 10. Tub teeth 105 are formed radially around theentrance in the rear of the shaft penetration 104 of the tub 10. In thewashing and rinsing modes, as will be described below, the tub teeth 105are coupled with the deceleration coupling unit 20, thereby allowing thedeceleration coupling unit 20 to decelerate the rotation of the shaft11. A spring support 106 is formed in a step shape on the inside of theshaft penetration 104, to support an end of a spring 24.

FIG. 5 is an exploded perspective view illustrating the drivingapparatus 1 for a washing machine according to the present invention.

As illustrated in FIG. 5, the driving apparatus 1 for a washing machineaccording to the present invention includes the tub 10, decelerationcoupling unit 20, stator assembly 30 and rotor assembly 40. The shaft 11penetrates the tub 10, and the tub 10 supports the rotation of the shaft11. The deceleration coupling unit 20 is positioned in a central space33 of the space assembly 30 and moves frontward or rearward by the leverunit 300. The stator assembly 30 is fixedly coupled to the tub 10. Thelever unit 300 is coupled to the stator assembly 30 to move thedeceleration coupling unit 20 frontward or rearward. The rotor assembly40 rotates in the position surrounding the stator assembly 30. The rearportion of the shaft 11 penetrates the rotor assembly 40. The rotorassembly 40 is not fixedly coupled with the shaft 11, but the rotationof the shaft 11 is supported by an end bearing 44 installed in thecenter of the rotor assembly 40. A fastening means 45 is coupled to therear end of the shaft 11, thereby preventing separation of the rotorassembly 40 from the rear portion.

The front end of the shaft 11 is a washing tub coupling 111, to whichthe washing tub (not illustrated) is fixed to rotate the shaft 11 andwashing tub together. The rear end of the shaft 11 is a fastener 112 towhich the fastening means 45 such as a nut is coupled. The middleportion of the shaft 11 forms a shaft spline 113 arranged in the axialdirection, and a coupling stopper 114 is formed in a step shape in frontof the shaft spline 113. The deceleration coupling unit 20 is coupled tothe shaft spline 113 movably in the axial direction within a limiteddistance. The coupling stopper 114 may limit frontward movement of thefront end of the deceleration coupling unit 20. The front portion of theshaft 11 is rotatably supported by the tub bearing 12, and the rearportion of the shaft 11 is rotatably supported by the end bearing 44 ofthe rotor assembly 40.

The deceleration coupling unit 20 is spline-coupled with the shaft 11 tobe movable frontward or rearward in the axial direction within a limiteddistance. The deceleration coupling unit 20 is positioned in the centralspace 33 of the stator assembly 30. The spring 24 is positioned betweenthe spring support 106 stepped inward the shaft penetration 104 of thetub 10 and the front surface of the deceleration coupling unit 20, toapply a force to push the deceleration coupling unit 20 rearward.Accordingly, when the deceleration coupling unit 20 is positioned to theside of the tub 10, the spring 24 is compressed. The detailed structuresof the deceleration coupling unit 20, stator assembly 30 and rotorassembly 40 will be described below by referring to each drawing.

FIG. 6 is a front perspective view illustrating the decelerationcoupling unit 20 of the driving apparatus 1 for a washing machineaccording to the present invention, FIG. 7 is a rear perspective viewillustrating the deceleration coupling unit 20, and FIG. 8 is anexploded perspective view illustrating the deceleration coupling unit20.

Referring to FIG. 6 to FIG. 8, the deceleration coupling unit 20according to the present invention includes a cup-shaped couplinghousing 21, a coupling cap 22 coupled to the front of the couplinghousing 21 and a carrier 23 received in the coupling housing 21. A sungear through hole 211 is formed in the center on the rearward bottomsurface of the coupling housing 21. A sun gear 432 of the rotor assembly40 penetrates through the sun gear through hole 211.

A flange 212 protrudes radially around the front end of the couplinghousing 21. The deceleration coupling unit 20 is movable frontward by afrontward force applied to the rear portion of the flange 212 by thelever unit 300. The deceleration coupling unit 20 is movable rearward bya compressive force of the spring 24. The coupling cap 22 is coupled tothe front of the coupling housing 21. A central hole 221 is formed inthe center of the coupling cap 22, through which a shaft receiver 232 aof the carrier 23 penetrates. A flange coupling 222 is formed around thecoupling cap 22 to fit in the flange 212, and first teeth 223 are formedin the shaft direction from the circumference of the flange coupling222. The first teeth 223 have a shape to be engaged with the tub teeth105. Accordingly, when the deceleration coupling unit 20 is positionedto the side of the tub 10 such that the first teeth 223 are engaged withthe tub teeth 105, the coupling housing 21 is not rotatable.

An inner gear 213 is formed around the inner wall of the couplinghousing 21. The inner gear 213 preferably has a spline shape in theaxial direction. The coupling housing 21 rotates together with thecarrier 23 in a state where the inner gear 213 is engaged with planetarygears 233 of the carrier 23, or only the carrier 23 rotates in the innergear 213 in a state where the coupling housing 21 is not rotatable, soas to decelerate the shaft 11.

To this end, the carrier 23 includes a first carrier body 231 of a ringshape, positioned in the rear side, a second carrier body 232 coupled tothe front of the first carrier body 231, planetary gears 233 rotatablycoupled to the front of the first carrier body 231, and planetary gearshafts 234 fixed to the first carrier body 231 to support the rotationof the planetary gears 233.

A sun gear through hole 231 a is formed in the center of the firstcarrier body 231. The shaft receiver 232 a protrudes frontward in thecenter of the second carrier body 232. Preferably, the shaft receiver232 a is exposed from the front of the central hole 221 of the couplingcap 22. A plurality of supports 232 b extending rearward are formedaround the second carrier body 232 such that the second carrier body 232is coupled with the first carrier body 231, and also the planetary gears233 are exposed from the circumference of the carrier 23. Of course,some or all of the supports 232 b may be formed in the second carrierbody 232.

A carrier spline 232 c is formed in the shaft direction on the innercircumferential surface of the shaft receiver 232 a. The carrier spline232 c is engaged with the shaft spline 113 such that the decelerationcoupling unit 20 is movable frontward or rearward within a limiteddistance. The sun gear 432 of the rotor assembly 40 penetrates throughthe sun gear through hole 211 of the coupling housing 21 and the sungear through hole 231 a of the first carrier body 231, so to be engagedwith the inside of the plurality of planetary gears 233. Accordingly,the rotation of the sun gear 432 causes the rotation of the carrier 23by the planetary gears 233. In the case where the coupling housing 21 isfixed, the planetary gears 233 of the carrier 23 are engaged with theinner gear 213 to rotate, the rotation of the carrier 23 is slower thanthe rotation of the sun gear 432, and the decelerated rotation isdelivered to the shaft 11 through the shaft spline 113 engaged with thecarrier spline 232 c. In the case where the coupling housing 21 isrotatable, the rotation of the sun gear 432 drives the rotation of theplanetary gears 232 and inner gear 213 together, and accordingly, therotation speed of the shaft 11 through the shaft spline 113 engaged withthe carrier spline 232 c is the same as the rotation speed of the sungear 432.

FIG. 5 and FIG. 8 illustrate four planetary gears 233, but the number ofplanetary gears are not necessarily limited to four. Three, five or sixplanetary gears may be applied variously according to need.

FIG. 9 is a perspective view illustrating the stator assembly 30 of thedriving apparatus 1 for a washing machine according to the presentinvention.

Referring to FIG. 9 along with FIG. 5, the stator assembly 30 accordingto the present invention includes an insulator 31 surrounding a statorcore (not illustrated). A lever unit coupling 32 is positioned in thecenter of the insulator 31. The central space 33 denotes an empty spacein the center of the stator assembly 30, and the deceleration couplingunit 20 is positioned in the space. The lever unit 300 coupled to thelever unit coupling 32 is operated to push the deceleration couplingunit 20 frontward. The arranging protrusion 103 a of the tub 10 isinserted in the arranging hole 34, and the coupling hole 35 ispositioned to communicate with the coupling hole 103 b, allowing a bolt,etc. to be coupled thereto.

The lever unit 300 includes a lever holder 310, a first lever 320 and asecond lever 330. The lever holder 310 is fixed to the lever unitcoupling 32 in the insulator 31 of the stator assembly 30. The firstlever 320 and second lever 330 are rotatably hinged to the lever holder310, rotate within a predetermined range, and communicate with eachother, as will be described below.

FIG. 10 is a side view illustrating the principle of operating the leverunit 300 of the driving apparatus 1 for a washing machine according tothe present invention.

As illustrated in FIG. 10, the lever unit 300 according to the presentinvention includes the lever holder 310 fixed to the lever unit coupling32 of the insulator 31, the first lever 320 hinged to the front side ofthe lever holder 310 and the second lever 330 hinged to the rear side ofthe lever holder 310.

The first lever 320 is hinged to the lever holder 310 by a first hinge321. Likewise, the second lever 330 is hinged to the lever holder 310 bya second hinge 331. When a lever operator 323 of the first lever 320operates from position A to position B, the first lever 320 rotates bythe first hinge 321, and a contact 322 in the rear side of the firstlever 320 also rotates. When the contact 322 rotates and pushes acontact surface 333 of the second lever 330, the second lever 330rotates with respect to the second hinge 331, and a lift 332 of thesecond lever 330 moves from position A′ to position B′. By operation ofthe first lever 320 and second lever 330, the deceleration coupling unit20 moves rearward from frontward to be positioned. The lift 332preferably has a U-shape when viewed from the front.

FIG. 11 is a side view illustrating the operation of the lever unit 300and deceleration coupling unit 20 of the driving apparatus 1 for awashing machine according to the present invention in a washing orrinsing mode, and FIG. 12 is a side view illustrating the operation in adewatering mode.

FIG. 11 illustrates the structure when the first lever 320 and secondlever 330 in FIG. 10 are in positions A and A′, respectively. In FIG.11, the lift 332 of the second lever 330 presses the flange 212 of thedeceleration coupling unit 20 to push the deceleration coupling unit 20frontward. In this state, the spring 24 is compressed between the springsupport 106 of the tub 10 and the coupling cap 22 of the decelerationcoupling unit 20. FIG. 11 shows the state in the washing or rinsingmode. When the operation is switched to the dewatering mode, the stateis transferred to a state as illustrated in FIG. 12.

Specifically, FIG. 12 illustrates the structure when the first lever 320and second lever 330 are in positions B and B′, respectively, byoperation of the lever unit 300. In FIG. 12, the lift 332 of the secondlever 330 moves rearward from the flange 212 of the decelerationcoupling unit 20, and the deceleration coupling unit 20 moves rearwardby the compressive force of the spring 24 compressed in the washing orrinsing mode. FIG. 12 shows the state in the dewatering mode.

FIG. 13 is a perspective view illustrating the rotor assembly 40 of thedriving apparatus 1 for a washing machine according to the presentinvention, and FIG. 14 is a cross-sectional view.

As illustrated in FIG. 13 and FIG. 14, the rotor assembly 40 accordingto the present invention includes a cup-shaped rotor housing 41, aplurality of magnets 42 attached to the inner wall of the rotor housing41, and a sun gear unit 43 formed in the center of the rotor housing 41.

The sun gear unit 43 is illustrated in FIG. 5 as a member independentfrom the rotor housing 41, but is not necessarily limited to such form.The sun gear unit 43 may be manufactured as a molded article integratedwith the rotor housing 41 by locating the rotor housing 41 in aninjection mold.

The sun gear unit 43 includes a main body 431, a sun gear 432 and ashaft penetration 433. The main body 431 is fixedly positioned in thecenter of the rotor housing 41, rotating integrally with the rotorhousing 41. The end bearing 44 is inserted in the rear of the main body431 thereinside. The shaft penetration 433 is formed in the center ofthe sun gear 432. The shaft 11 penetrates through the shaft penetration433 and is rotatably supported by the end bearing 44. Thanks to such astructure, the torque is not transmitted directly to the shaft 11 whenthe rotor housing 41 rotates. The rotor housing 41 and shaft 11 arecoupled to each other to rotate independently. The rotation of the rotorhousing 41 causes the rotation of the sun gear 432, and the rotation ofthe sun gear 432 causes the rotation of the carrier 23. Accordingly, theshaft 11 spline-coupled with the carrier 23 rotates by rotation of thecarrier 23. The independent coupling between the rotor housing 41 andshaft 11 allows the rotation speed of the shaft 11 to decelerate withrespect to the rotation speed of the rotor housing 41.

The sun gear 432 has an outer shape to be engaged with the inside of theplurality of planetary gears 233 installed in the carrier 23 of thedeceleration coupling unit 20. The fastening means 45, components suchas a washer or nut, is coupled to the rear end of the shaft 11, therebypreventing the end bearing 44 from being pushed rearward and the shaft11 from being moved frontward.

Rotor teeth 46 are formed in the center of the rotor housing 41 andaround the sun gear 432. The rotor teeth 46 are engaged with secondteeth 214 of the deceleration coupling unit 20 when the decelerationcoupling unit 20 moves rearward. When the rotor housing 41 rotates whilethe rotor teeth 46 and second teeth 214 are engaged with each other, thedeceleration coupling unit 20 rotates accordingly.

FIG. 15 is a cross-sectional view illustrating the structure when thedriving apparatus 1 for a washing machine according to the presentinvention operates in a washing or rinsing mode.

Referring to FIG. 15, in the washing or rinsing mode, in the drivingapparatus 1 for a washing machine according to the present invention,the first lever 320 of the lever unit 300 operates such that the secondlever 330 moves the deceleration coupling unit 20 frontward. Here, thespring 24 is compressed, and the first teeth 223 formed in the couplingcap 22 of the deceleration coupling unit 20 are brought into engagementwith the tub teeth 105 formed in the tub 10.

In this state, when power is applied to the stator assembly 30 to rotatethe rotor housing 41 of the rotor assembly 40, the sun gear 432 of thesun gear unit 43 rotates together, and the plurality of planetary gears233 engaged with the sun gear 432 rotate. The coupling housing 21coupled with the coupling cap 22 is forced not to rotate. Accordingly,the carrier 23 rotates at a decelerated speed in the coupling housing21. Since the carrier spline 232 c formed on the inside of the shaftreceiver 232 a of the carrier 23 is engaged with the shaft spline 113,the decelerated rotation of the carrier 23 is intactly delivered to therotation of the shaft 11. The decelerated rotation of the shaft 11causes the decelerated rotation of the washing tub (not illustrated)coupled to the front of the shaft 11. Accordingly, the washing andrinsing modes are performed at a low speed.

FIG. 16 is a cross-sectional view illustrating the structure when thedriving apparatus 1 for a washing machine according to the presentinvention operates in a dewatering mode.

As illustrated in FIG. 16, when the operation is switched to thedewatering mode, the first lever 320 of the lever unit 300 operates inthe arrow direction such that the lift 332 of the second lever 330rotates rearward. Here, the spring 24 compressed pushes the decelerationcoupling unit 20 rearward. The coupling cap 22 engaged with the tubteeth 105 of the tub 10 is separated therefrom. The coupling housing 21moves rearward such that the second teeth 214 formed in the couplinghousing 21 are engaged with the rotor teeth 46 formed in the center ofthe rotor housing 41. Of course, a structure where the lift 332 of thesecond lever 330 is coupled with the coupling housing 21 without thespring 24 for movement can be considered.

In this state, when power is applied to the stator assembly 30 to rotatethe rotor housing 41 of the rotor assembly 40, the sun gear 432 of thesun gear unit 43 rotates together, and the plurality of planetary gears233 engaged with the sun gear 432 rotate. Since the second teeth 214 ofthe coupling housing 21 are engaged with the rotor teeth 46 of the rotorhousing 41, the rotation of the rotor housing 41 directly causes therotation of the coupling housing 21.

Accordingly, the carrier 23, coupling housing 21 and rotor housing 41rotate at the same speed. Since the carrier spline 232 c formed on theinside of the shaft receiver 232 a of the carrier 23 is engaged with theshaft spline 113, the rotation of the carrier 23 is intactly deliveredto the rotation of the shaft 11. Accordingly, the rotation speed of therotor housing 41 is the same as the rotation speed of the shaft 11. Thewashing tub (not illustrated) coupled to the front of the shaft 11 alsorotates at the same speed as the rotor housing 41. Accordingly, thedewatering mode is performed at a high speed.

The detailed description of the present invention described as abovesimply explains examples for understanding the present invention, butdoes not intend to limit the scope of the present invention. The scopeof the present invention is determined by the accompanying claims.Additionally, it should be construed that a simple modification orchange falls under the protection scope of the present invention.

The invention claimed is:
 1. A driving apparatus for a washing machine,comprising: a tub; a stator assembly coupled to the tub; and a rotorassembly positioned outside the stator assembly, the apparatus furthercomprising a deceleration coupling unit positioned in a central space ofthe stator assembly, wherein the deceleration coupling unit comprises acarrier, wherein the carrier has a plurality of planetary gearsinstalled therein and comprises a shaft receiver having a carrier splineon the inside, wherein the deceleration coupling unit further comprisesa coupling housing receiving the carrier inside and having an inner gearengaged with the outer portions of the plurality of planetary gears, andwherein a lever unit is coupled to an insulator of the stator assemblysuch that the lever unit moves the coupling housing frontward orrearward.
 2. The driving apparatus for a washing machine according toclaim 1, further comprising a shaft penetrating the carrier and therotor assembly, wherein the shaft has a shaft spline formed in aposition fitting into the carrier spline.
 3. The driving apparatus for awashing machine according to claim 2, wherein the shaft penetratesthrough a shaft penetration of a sun gear protruding frontward in therotor assembly.
 4. The driving apparatus for a washing machine accordingto claim 3, wherein the sun gear has an outer shape to be engaged withthe inner portions of the plurality of planetary gears.
 5. A drivingapparatus for a washing machine, comprising: a tub; a stator assemblycoupled to the tub; and a rotor assembly positioned outside the statorassembly, the apparatus further comprising a deceleration coupling unitpositioned in a central space of the stator assembly, wherein thedeceleration coupling unit is movable frontward or rearward in the tuband rotor assembly, and the deceleration coupling unit decelerates therotation of a shaft penetrating the tub in a washing mode.
 6. Thedriving apparatus for a washing machine according to claim 5, whereinthe deceleration coupling unit comprises a carrier, wherein the carrierhas a plurality of planetary gears installed therein and comprises ashaft receiver having a carrier spline on the inside.
 7. The drivingapparatus for a washing machine according to claim 6, wherein thedeceleration coupling unit further comprises a coupling housingreceiving the carrier inside and having an inner gear engaged with theouter portions of the plurality of planetary gears.
 8. The drivingapparatus for a washing machine according to claim 7, wherein a leverunit is coupled to an insulator of the stator assembly such that thelever unit moves the coupling housing frontward or rearward.
 9. Thedriving apparatus for a washing machine according to claim 5, whereinthe shaft penetrates a shaft penetration of a sun gear protrudingfrontward in the rotor assembly.